Mixed fishway capable of adapting to upstream large-water-level amplitude variation
Technical Field
The invention relates to a mixed fishway capable of adapting to upstream large water level amplitude variation, which is used for the construction of fish passing facilities in hydraulic and hydroelectric engineering and belongs to the field of hydraulic engineering.
Background
The fishway is an important facility for communicating a fish migration route, has irreplaceable significance in communicating the fish migration route on a low-water-head hydro hub, and is one of key contents of ecological protection and restoration technologies of hydraulic engineering.
The country has built a large amount of reservoir dam projects for 60 years, and the reservoir dams play a great role in flood control, irrigation, power generation, water supply, shipping, aquaculture and the like, and obtain remarkable social and economic benefits. However, the existence of a large number of reservoirs and gate dams blocks the continuity of rivers, changes the natural state of water and sand and the natural hydrological process of the rivers, damages habitats of aquatic organisms, and greatly reduces the number of fish populations due to the serious inhibition of upward tracking and downward flow, so that a lot of rare fish resources are endangered. For example, in the northeast of Yangtze river in China, a series of hydraulic projects such as the Wanfu gate and the like are built in 1959, migration routes of juvenile crabs, young eels, hairtails and the like are cut off, economic fishes in the regions such as Gaoyou lakes, Hongze lakes and the like are rapidly reduced, after a Taiping gate fishway is built in 1973, the migration routes of fishes are restored again, and in addition, other auxiliary measures are added, so that the fishery output of the lake regions is gradually restored. More successful cases of the fishway are available in foreign countries, such as the fishway of the Ponnevell dam in the United states, and 65 ten thousand fish tails are passed in average year; the fishways of the Mecany dam in the United states have 106 thousands of fishes every year, and the construction of the fishways creates good conditions for fishery production and river ecology restoration.
The guide for fishway design in hydraulic and hydroelectric engineering (SL 609 and 2013) provides: when the upstream water level amplitude is large in the fish season, a plurality of fishway outlets with different positions and elevations are arranged. Fish passes-Design, dimensions and monitoring published by the food and agriculture organization of the United nations stipulates that the fishway outlet is preferably designed into a vertical seam type, and a plurality of outlets are arranged if the water level amplitude exceeds 1 m. The number of reservoirs in China is large, some reservoirs are influenced by daily regulation of a power station, the variation of the water level of the reservoirs reaches more than 10 meters, and the huge variation of the water level brings huge difficulty to the design of a fishway outlet. If, according to conventional design, the fishway exit would be as many as 10 or more, it is very difficult, both from a design and from a management perspective. Therefore, the invention provides the mixed fishway capable of adapting to the upstream large-water-level amplitude, the complex outlet type of multiple outlets of the fishway can be simplified into the simple fishway single-outlet type, the fishway design can be simplified, the fishway management is convenient, and the mixed fishway has important significance for the fishway construction in China.
Disclosure of Invention
The invention aims to provide a mixed fishway type capable of adapting to upstream large water level amplitude, the fishway can adapt to upstream large water level amplitude, fishway design is simplified, and fishway operation and management are facilitated.
The mixed fishway adapting to the upstream large water level amplitude sequentially comprises from downstream to upstream: a fishway partition section, a fishway residence pond section and a fishway lock chamber section;
wherein the interior of the fishway partition section is a normal fishway, which belongs to a transition section of the normal fishway and a fishway residence tank section, and the downstream of the transition section is connected with the normal fishway;
the fishway residence pond section is connected with the fishway partition section and the fishway lock chamber section and is a rectangular channel for temporarily retaining and resting fishes traced upwards through the fishway; the fishway resident pool section is provided with a resident pool stilling pool and a resident pool water replenishing pipe, the resident pool water replenishing pipe is communicated with an upstream pool area, and a self-adaptive water delivery valve is arranged to provide stable and constant water volume and realize continuous fish luring;
the fishway staying pool section is flat and is provided with a staying pool section fish catching grid for catching fish in the staying pool section into the fishway lock chamber section;
the fish catching grid of the staying pool section is an integral lifting type fish catching grid;
specifically, the method comprises the following steps: grid, horizontal sliding rod, actuating lever, driving motor, grid spoke, both ends support, pulley, vertical hoist engine, driving motor fixes on the support of one end, links to each other with the actuating lever through the chain, and the actuating lever is the threaded rod, passes the motion bolt, motion bolt and grid fixed connection, and the grid four corners sets up four locating holes, and horizontal sliding rod passes above-mentioned locating hole, and grid spoke connects motion bolt and locating hole.
The supports at the two ends are 4 steel piles fixed on the upper stream and the lower stream of the resident pool section, the height of each steel pile is 2.2 times of that of the resident pool section, a sliding sleeve is arranged outside each steel pile, the outer side of each sliding sleeve is welded with a horizontal sliding rod, and each sliding sleeve is sleeved on each steel pile; two ends of the two horizontal sliding rods positioned on the upper part are provided with hanging rings which are connected with a chain, and the chain bypasses the pulley and is connected to a vertical winch.
When the fish catching grid of the staying pool section is lifted out of the staying pool section, the vertical winch works to tighten the chain, the grid, the horizontal sliding rod, the driving motor, the grid spokes and the brackets at the two ends are integrally pulled out of the water surface, the sliding sleeve slides on the steel pile, the on-off limiter is arranged at the highest point of the steel pile, when the sliding sleeve reaches the highest point, the vertical winch is powered off and automatically locked, and the whole frame is finally limited to the highest point of the steel pile; the driving motor works to push the threaded rod to rotate to drive the moving bolt, so that the grid slides downstream along the horizontal sliding rod, and the fish catching grid enters a reset state.
When the fish catching grid at the staying pool section enters the staying pool section, the vertical winch firstly tightens the chain to trigger the locking mechanism, opens the locking device, then releases the chain to catch the whole fish catching grid and put into water, and when the device is completely put into water; the driving motor works reversely to push the threaded rod to rotate to drive the moving bolt, so that the grid slides upstream along the horizontal sliding rod, and the fish catching grid enters a fish catching state.
A resident pool section lifting gate is arranged at the upstream of the fishway resident pool section and is used for separating the resident pool section from a fishway gate chamber section;
the fishway lock chamber section is positioned between the fishway resident pond section and the upstream reservoir, and a lock chamber section gate is arranged upstream to separate the lock chamber section from the upstream reservoir so as to adapt to the large amplitude water level of the upstream reservoir;
the fishway lock chamber section is provided with a lock chamber section stilling pool and a lock chamber section water replenishing pipe, and the lock chamber section water replenishing pipe is communicated to an upstream reservoir area and is provided with a self-adaptive water delivery valve.
The fish way lock chamber section is also provided with a lock chamber section horizontal fish driving grid for driving the fish in the lock chamber section into an upstream reservoir area;
the fish way lock chamber section is also provided with a lock chamber section vertical fish catching grid used for catching fish at the bottom of the lock chamber section to the surface.
The operation steps of the mixed fishway are as follows:
(1) fish luring and collecting stage: closing the lifting gate of the resident pool section, closing the gate of the lock chamber section, opening the water replenishing pipe of the resident pool all the time, and enabling water flow to flow out of the stilling pool of the resident pool to lure fish; the fish enters the fishway staying pool section through the fishway partition section;
(2) a fish catching stage A: the fishway staying pool section fish driving grid enters the fishway staying pool section, the fishway staying pool section runs upstream from the downstream of the fishway staying pool section, and fish are driven into the fishway lock chamber section;
(3) a water level adjusting stage: closing the lifting gate of the fishway resident pond section, slowly opening the sluice chamber section water replenishing pipe according to the designed valve opening speed, and slowly raising the water level in the fishway sluice chamber section to be equal to the water level of an upstream reservoir; meanwhile, the fish repelling grid of the residence tank is lifted up again, the residence tank returns to the downstream and is kept open, and the residence tank section continuously lures fish;
(4) a fish catching stage B: closing the water conveying pipeline of the gate chamber section, enabling the fish catching grid of the fishway gate chamber section to enter the fishway gate chamber section from the downstream of the fishway gate chamber section, opening the gate of the fishway gate chamber section, and enabling the fish catching grid of the gate chamber section to move upstream to catch the fish into an upstream reservoir;
(5) a water draining stage: and pumping water conservancy water pumps in the fish way lock chamber section into a downstream river channel.
And repeating the steps to ensure that the mixed fishway continuously works.
Typical hydraulic indexes of the water filling and draining process of the fish way lock chamber section comprise water delivery flow Q and valve opening time tvTotal water delivery time t and water delivery power EtUnit water body power dissipation E, chamber water level rising rate and the like, and all indexes comprehensively reflect the operating characteristics of the fish gate, wherein the water delivery power EtRepresenting the amount of work done in the unit time of the water conveying body; the unit water body power dissipation E represents the water body turbulence condition in the lock chamber (the larger the unit water body power dissipation is, the larger the water flow turbulence intensity is), and the calculation is respectively as follows:
water delivery power Et
Et=ρgQtht
In the formula EtWater flow power (W) at time t; qtWater flow rate (m) at time t3/s);htThe water level difference (m) between the reservoir water level and the chamber water level at the time t can be obtained from the chamber water level and time relation curve.
Specific water power dissipation E
E=Et'/Vt
Wherein E is the unit water power dissipation (W/m)3);Et' is the water flow power (W) of the water entering the lock chamber; vtLock chamber water volume (m) at time t3)。
Because fishes are extremely vulnerable to injury in a turbulent water body, the inventor obtains the following results through repeated experiments and calculation:
the fishway lock chamber and the fishway staying pool section meet the following control conditions in the water conveying process:
(1) the unit water body power dissipation E is less than 200W/m3When the conditions allow, the concentration is preferably less than 50W/m3;
(2) Water level amplitude delta h in fishway lock chambertThe requirement is less than 2.5 m/min;
(3) the flow velocity at any position in the water filling and draining process of the fish way lock chamber section is less than 1.5m/s, and the flow velocity is preferably less than 1m/s when the conditions allow.
The invention has the beneficial effects that:
the fishway gate chamber is arranged at the upstream section of the fishway, so that the problem that a plurality of fishway outlets are required to be arranged when the fishway is in large water level amplitude at the upstream is solved, the construction cost is greatly saved, and the pivot arrangement difficulty is reduced.
And the control conditions of the water conveying process of the fishway lock chamber and the fishway residence pond section are provided.
Drawings
FIG. 1 is a schematic top view of the present invention;
FIG. 2 is a schematic front view of the present invention;
FIG. 3 is a schematic view of the structure of the fish catching grid according to the present invention;
FIG. 4 is a schematic front view in cross section of the fish grating of the present invention;
FIG. 5 is a schematic top sectional view of the fish grating of the present invention;
FIG. 6 is a schematic side view of the fish grating of the present invention;
FIG. 7 is a schematic plan view of the lock chamber of the present invention;
FIG. 8 is a schematic front view of the chamber of the present invention.
Detailed Description
The invention will now be further described with reference to the accompanying drawings.
Example 1
A certain hub consists of a barrage, a flood discharge hole, a sand discharge hole, a power generation and water diversion system, a power station, a fish passing building and an ecological water discharge building. Total reservoir capacity of 2.0 hundred million m3For daily regulation of the reservoir, the daily variation of upstream water level is 14m, and the fish passing facility is designed to be capable of normally running under the condition that the reservoir water level fluctuates. The barrage is an asphalt core rock-fill dam with the maximum dam height of 62 m.
In order to adapt to the huge amplitude of the upstream water level, a mixed fishway type adapting to the large amplitude of the upstream water level is adopted, and the fishway with the total length of 6025.6m originally designed is shortened to 3500 m.
The mixed fishway adapting to the upstream large water level amplitude sequentially comprises from downstream to upstream: a fishway partition section 1, a fishway residence pond section 2 and a fishway lock chamber section 3;
wherein the fishway baffle section 1 is a normal fishway section and belongs to a transition section of a normal fishway and a fishway residence pond section 2, and the downstream of the transition section is connected with the normal fishway;
the fishway residence pond section 2 is connected with the fishway partition section 1 and the fishway lock chamber section 3 and is a rectangular channel for temporarily retaining and resting fishes going up through the fishway; the fishway resident pool section 2 is provided with a resident pool stilling pool 21 and a resident pool water replenishing pipe 22, the resident pool water replenishing pipe 22 is communicated to an upstream pool area, and a self-adaptive water delivery valve 20 is arranged to provide stable and constant water volume and realize continuous fish luring;
the fishway staying pool section 2 is flat and is also provided with a staying pool section fish catching grid 23 for catching fish in the staying pool section 2 into the fishway lock chamber section 3;
the fish catching grid 23 of the staying pool section is an integral lifting type fish catching grid;
specifically, the method comprises the following steps: grid A1, horizontal sliding rod A2, driving rod A3, driving motor A4, grid spoke A5, two-end bracket A6, pulley A7 and vertical winch A8, driving motor A4 is fixed on the bracket at one end and is connected with driving rod A3 through a chain, driving rod A3 is a threaded rod and penetrates through a moving bolt, the moving bolt is fixedly connected with grid A1, four positioning holes are formed in four corners of grid A1, horizontal sliding rod A2 penetrates through the positioning holes, and grid spoke A5 is connected with the moving bolt and the positioning holes.
The brackets at the two ends are 4 steel piles A61 fixed on the upper and lower streams of the resident pool section, the height of the steel pile A61 is 2.2 times of the height of the resident pool section, a sliding sleeve A62 is arranged outside the steel pile A61, the outer side of the sliding sleeve A62 is welded with a horizontal sliding rod A2, and a sliding sleeve A62 is sleeved on the steel pile A61; two ends of two horizontal sliding rods A2 at the upper part are provided with hanging rings which are connected with a chain, and the chain is wound around a pulley A7 and is connected on a vertical winch A8.
When the fish catching grid 23 of the staying pool section is lifted out of the staying pool section 2, the vertical winch A8 works to tighten the chain, the grid A1, the horizontal sliding rod A2, the driving rod A3, the driving motor A4, the grid spoke A5 and the brackets at the two ends are integrally pulled out of the water surface, the sliding sleeve A62 slides on the steel pile A61, the highest point of the steel pile A61 is provided with an on-off stopper, when the sliding sleeve A62 reaches the highest point, the vertical winch A8 is powered off and automatically locked, and the whole frame is finally limited to the highest point of the steel pile A61; the driving motor A4 works to push the threaded rod A3 to rotate, and the moving bolt is driven, so that the grid A1 slides downstream along the horizontal sliding rod A2, and the fish catching grid 23 enters a reset state.
When the fish catching grid 23 of the staying pool section enters the staying pool section 2, the vertical winch A8 firstly tightens the chain to trigger the locking mechanism, opens the locking device, then releases the chain to catch the whole fish catching grid 23 and puts the whole fish catching grid into water, and when the device is completely put into water; the driving motor A4 works reversely to push the threaded rod A3 to rotate, and the moving bolt is driven, so that the grid A1 slides upstream along the horizontal sliding rod A2, and the fish catching grid 23 enters a fish catching state.
A resident pond section lifting gate 24 is arranged at the upstream of the fishway resident pond section 2 and is used for separating the resident pond section 2 from the fishway lock chamber section 3;
the fishway lock chamber section 3 is positioned between the fishway resident pond section 2 and the upstream reservoir, and a lock chamber section gate 34 arranged upstream of the fishway lock chamber section separates the lock chamber section 3 from the upstream reservoir to adapt to the large amplitude water level of the upstream reservoir;
the fishway lock chamber section 3 is provided with a lock chamber section stilling pool 31 and a lock chamber section water replenishing pipe 32, the lock chamber section water replenishing pipe 32 leads to an upstream reservoir area, and is provided with a self-adaptive water delivery valve 30.
The fish way gate chamber section 3 is also provided with a gate chamber section horizontal fish catching grid 33 which is used for catching the fish in the gate chamber section 3 into an upstream reservoir area;
the fish way gate chamber section 3 is also provided with a gate chamber section vertical fish catching grid 35 for catching the fish at the bottom of the gate chamber section 3 to the surface.
The operation steps of the mixed fishway are as follows:
(1) fish luring and collecting stage: the resident pool section lifting gate 24 is closed, the gate chamber section gate 34 is closed, the resident pool water replenishing pipe 22 is always opened, and water flows out of the resident pool stilling pool 2 to lure fish; the fish enters a fishway resident pond section 2 through a fishway partition section 1;
(2) a fish catching stage A: the fishway staying pool section fish catching grid 23 enters the fishway staying pool section 2, runs upstream from the downstream of the fishway staying pool section 2, and catches fish into the fishway lock chamber section 3;
(3) a water level adjusting stage: closing the lifting gate 24 of the fishway resident pond section, slowly opening the gate chamber section water replenishing pipe 32 according to the designed valve opening speed, and slowly raising the water level in the fishway gate chamber section to be equal to the water level of the upstream reservoir; meanwhile, the fish repelling grid of the residence tank is lifted up again and returns to the downstream, the self-adaptive water delivery valve 30 is kept opened, and the residence tank section 2 continuously lures fish;
(4) a fish catching stage B: closing the lock chamber section water pipeline 32, enabling the fishway lock chamber section fish catching grid 33 to enter the fishway lock chamber section 3 from the downstream of the fishway lock chamber section 3, opening the fishway lock chamber section gate 34, and enabling the lock chamber section fish catching grid 33 to move upstream to catch fish into an upstream reservoir;
(5) a water draining stage: and pumping water conservancy water pumps in the fish way lock chamber section 3 into a downstream river channel.
And repeating the steps to ensure that the mixed fishway continuously works.
Typical hydraulic indexes of the water filling and draining process of the fish way lock chamber section 3 comprise water delivery flow Q and valve opening time tvTotal water delivery time t and total water delivery energy EtUnit water body power dissipation E, chamber water level rising rate and the like, and all indexes comprehensively reflect the operating characteristics of the fish gate, wherein the energy EtRepresenting the energy of the water conveying body; the unit water body power dissipation E represents the water body turbulence condition in the lock chamber (the larger the unit water body power dissipation is, the larger the water flow turbulence intensity is), and the calculation is respectively as follows:
water flow power Et
Et=ρgQtht
In the formula EtWater flow power (W) at time t; qtWater flow rate (m) at time t3/s);htThe water level difference (m) between the reservoir water level and the chamber water level at the time t can be obtained from the chamber water level and time relation curve.
Specific water power dissipation E
E=Et'/Vt
Wherein E is the unit water power dissipation (W/m)3);Et' is the water flow power (W) of the water entering the lock chamber; vtLock chamber water volume (m) at time t3)。
Because fishes are extremely vulnerable to injuries in a turbulent water body, the inventor obtains the following results through repeated experiments and calculation:
the fishway lock chamber and the fishway staying pool section meet the following control conditions in the water conveying process:
(1) the unit water body power dissipation E is less than 200W/m3When the conditions allow, the concentration is preferably less than 50W/m3;
(2) Water level amplitude delta h in fishway lock chambertThe requirement is less than 2.5 m/min;
(3) the flow velocity at any position in the water filling and draining process of the fish way lock chamber section is less than 1.5m/s, and the flow velocity is preferably less than 1m/s when the conditions allow.
Through calculation, the hydraulic indexes of the water delivery valve at the fish way lock chamber section at different opening rates are shown in table 1. As can be seen from Table 1, when the valve is opened for 1-3 min, the power dissipation E of the unit water body is more than 200W/m3Considering that the smaller the value, the better, the valve opening time is recommended to be 4min, and at this time, the water level variation Δ h in the fish way lock chambertAll satisfy less than 2.5m/min. The flow velocity at any position in the water filling and draining process of the fishway lock chamber under each working condition is less than 1 m/s.
TABLE 1 Main Hydraulic characteristic index of operation of fishway lock chamber section
Example two
A certain hub consists of a barrage, a power generation and water diversion system, a power station, a sluice gate, a fish passing building and the like. Total storage capacity of reservoir 1.0 hundred million m3For daily regulation of reservoir, the daily variation of upstream water level is 10m, and the fish passing facility is designed to be capable of normally running under the condition of reservoir water level fluctuation. The barrage is a concrete gravity dam with the maximum dam height of 50 m.
In order to adapt to the huge amplitude of the upstream water level, a 'mixed fishway capable of adapting to the large amplitude of the upstream water level' is designed, and after the fishway is adopted, the fishway with the total length of 5200m in the original design can be greatly shortened (nearly half of the fishway length is shortened). On the basis of the embodiment 1, the sizes of the stilling pool at the water outlet of the retention pool and the stilling pool at the water outlet of the fishway gate chamber section are increased (the energy dissipation efficiency can be further improved by continuously adding facilities such as an energy dissipation sill and the like in the pool chamber), and the lengths of the retention pool sections are shortened due to the limitation of engineering arrangement. In order to improve the fish catching effect of the fish way lock chamber section, a vertical fish catching grid is added, as shown in fig. 7 and 8. In the concrete operation, after the fish enters the fishway lock chamber section, the resident pond section lifting gate is closed, water is filled into the fishway lock chamber section, the water level is flushed with the upstream reservoir, the vertical fish catching grid is lifted, the fishway lock chamber section upstream gate is opened, the fish is caught to the water surface, the horizontal fish catching grid is started, and the fish is caught out of the lock chamber.